Maaswinkel Hans, Ren Jason Q, Li Lei
Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA.
J Neurocytol. 2003 Nov;32(9):1107-16. doi: 10.1023/B:NEUR.0000021905.33091.f1.
We describe here the morphological and functional alterations of the retina of mutant zebrafish, night blindness c ( nbc ). The nbc mutant was isolated from the F1 generation of N -ethyl- N -nitrosourea mutagenized founders. Visual sensitivity of wildtype and heterozygous ( nbc (+/-)) mutant fish was determined using a behavioral assay based on visually mediated escape responses. Histology, immunocytochemistry, and electroretinography were used to study structural and functional changes of the outer retina. The behavioral visual response of nbc (+/-) mutants started to deteriorate at 12 months of age. Considerable variations existed between the extents of retinal degeneration of individual fish. In the most severe cases, both rod and cone outer segments were degenerated. In moderate cases, only rod outer segments were affected. Yet in other cases, no degeneration was detected. The retina of homozygous ( nbc (-/-)) larvae had a normal appearance. However, they develop abnormally and died before 9 days post fertilization. In conclusion, nbc causes late-onset and progressive dominant retinal degeneration of both rod and cone photoreceptor cells. However, nbc is not a retina-specific gene, as the homozygous fish displayed extra-retinal defects.
我们在此描述了突变斑马鱼夜盲症c（nbc）视网膜的形态和功能改变。nbc突变体是从经N-乙基-N-亚硝基脲诱变的奠基者的F1代中分离出来的。使用基于视觉介导的逃避反应的行为测定法来确定野生型和杂合（nbc(+/-)）突变体鱼的视觉敏感性。组织学、免疫细胞化学和视网膜电图被用于研究视网膜外层的结构和功能变化。nbc(+/-)突变体的行为视觉反应在12个月大时开始恶化。个体鱼的视网膜退化程度存在相当大的差异。在最严重的情况下，视杆和视锥细胞的外段都发生了退化。在中度情况下，只有视杆细胞的外段受到影响。然而在其他情况下，未检测到退化现象。纯合（nbc(-/-)）幼虫的视网膜外观正常。然而，它们发育异常并在受精后9天前死亡。总之，nbc导致视杆和视锥光感受器细胞迟发性和进行性显性视网膜退化。然而，nbc不是一个视网膜特异性基因，因为纯合鱼表现出视网膜外缺陷。
